The “Squawk on the Street” crew weighs in on bitcoin’s enormous surge as the digital currency tops $15,000. This is one of the least functional markets I’ve ever seen, says Cramer. » Subscribe to CNBC: http://cnb.cx/SubscribeCNBC About CNBC: From ‘Wall Street’ to ‘Main Street’ to award winning original documentaries and Reality TV series, CNBC has…